Starting device for internal combustion engines



June 12, 1934. A. CALLSEN ET AL 1,962,706

STARTING DEVICE FOR INTERNAL COMBUSTION ENGINES Filed July 8, v1932 2 Sheets-Sheet 1 June 12, 1934. r A CALLSEN ET AL 1,962,706

STARTING DEVICE FOR INTERNAL C OMBUSTION ENGINES Filed July 8, 1932 2 Sheets-Sheet 2 Patented June 12, 1934 UNITED STATES STARTING DEVICE FOR INTERNAL COMBUSTION ENGINES Albert Callsen, Stuttgart, and Ernst Klemm, Cannstatt, Germany, assignors to Robert Bosch Aktlengesellschaft, Stuttgart, Germany Application July 8, 1932, Serial No. 621,446 In Germany September 7, 1931 8 Claims. (01. 290+38) The present invention relates to starting devices for internal combustion engines, in which an inertia mass is brought to a high speed of rotation when the starting motor is running idle,

Q and is then coupled with ,a pinion which can be engaged with a toothed wheel of the engine' In a known arrangement the inertia mass is connected-by a centrifugal clutch with an engageable pinion. 'This clutch puts the inertia mass 10 in driving connection with the pinion after the mass has been brought to full speed. This arrangement has the drawback that the inertia mass is not automatically disconnected from the pinion when the engine starts and overtakes the pinion. If the driver forgets to disengage the pinion at the proper time, the inertia mass may acquire a dangerous speed. In another known arrangement the inertia mass is connected by a disconneotible clutch through a transmission gearing which is permanently connected with the disconnectible part 'of the clutch, and a freewheel mounted on the crank-shaft of the engine connected with the starting motor. This arrangement is practically unimportant, as a freewheel which during the entire period of travel is operative in the overtaking position is very soon destroyed.

The drawbacks mentioned in the known devices are avoided in the arrangement according to the.

invention. It consists in that the pinion, the free-wheel and the clutch together can be adjusted by a single lever, and the starting motor is only cut in when the clutch is disengaged.

In the accompanying drawings an example of construction of the invention is diagrammatically shown. Figures 1-3. show a starting device according to the invention in various working positions.

In the drawings, a is an electrical starting motor, and b an inertia mass, which is keyed on the armature shaft 0. On the starting shaft, which in the present example is shown as an extension of the armature shaft, there is also mounted a cone clutch d, one part c of which is only axially displaceable on the shaft, and is driven from the shaft by a feather f, whilst the other part 9 of the clutch is mounted on a sleeve h axially displaceable on the armature shaft and also revoluble about the shaft. On the clutch disc 9 a stop member bl is secured, which limits the distance apart of the two parts 6 and g of the clutch. The axial displacement of the clutch towards the outer end of the shaft of the starting motor is limited by a stop i at the end of that shaft 0.

On the sleeve h is mounted a free-wheel clutch k. One part I of the free-wheel clutch is secured against rotation on the sleeve, whilst the other I part m is firmly connected with the pinion 11. re-

voluble on the sleeve. In this arrangement the 30 part 1 may be said to be the driving element and the part m the driven element of the free-wheel clutch. The pinion and the free-wheel are not displaceable axially in relation to the sleeve h.

o is the toothed fly-wheel rim of an internal combustion engine with which the pinion can be engaged.

A lever p serves for engaging the pinion and the clutch, the fork of which lever engages in an annular groove q in the clutch part c. A rod r is pivotally connected with the lever. At the free end of the rod an insulating piece t carrying a contact piece s is secured. The insulating piece has oblique surfaces di and e1 at its ends. In the path of the insulating piece a pair of contacts u, 76

1) is arranged. The contact 0 is connected with I one terminal of the starter a, the other terminal of the winding being earthed. The contact u is mounted on a springy yoke .r, revoluble about a pin w, and the free end of the yoke is so curved that it forms two sloping surfaces y and z. The free end of the yoke lies in such a way that the surfaces 11 and z co-operate with the inclined surfaces (11 and e1 of the insulating piece. The sloping surfaces y and z are insulated on theside fac-- ing the insulating piece by layers of insulating material. A spring (11 on the springy yoke presses the contact u against the insulating piece if when this latter is between the two contacts u and v. The contact u is connected with one pole of a battery 01, whilst the other pole of the battery is earthed.

The starting device works in the following way: In order to start the motor, the lever p is rocked from the position in Fig. 1 to the right into the position according to Fig. 2. By this means the clutch part e is pressed against the other clutch part g and pushes this latter with the pinion n located on the sleeve h and the free-wheel m towards the toothed rim 0 until the sleeve It strikes 100 against the stop 2'. During this displacement the pinion is engaged in the toothed rim 0 of the fly- -wheel. The insulating piece t displaced towards the right on the movement of the lever p turns the spring yoke x about the pin w, so that the curved end :1 z rubs on the insulating piece, whereby the contact u is raised and maintained in raised position until the contact piece s moves past below the contact u without touching this latter into thefposition shown in Fig. 2. The lever p i now moved back again so far until the clutch disc e strikes the stop in and thereby releases the clutch 12. At the same time the contact piece s of the insulating piece 23 has come between the contacts u, 1) (Fig. 3) and has connected the starting motor with the battery. The inclined surface (11 of the insulating piece in this position presses against the surface a and thereby increases the pressure contact of the contact u. As soon as the starting motor has brought the inertia mass to a high speed, the lever p is again brought into the position shown in Fig. 2 and thereby the clutch d is cut in and the inertia mass connected in a driving manner through the free-wheel clutch k with the pinion and the internal combustion engine started. When the engine runs under its own power the pinion owing to the free-wheel k is alone idly-driven. The lever p can now be again brought into the initial position, during which the clutch part e, by the stop in, pulls back the sleeve h with the pinion n thereon and the free-wheel k, and the insulating piece it slides under the springy end of the yoke at, so that the parts are restored to their initial positions shown in Fig. 1.

We declare that what we claim is:

1. A starting device for internal combustion engines comprising a starting motor, an inertia mass driven by said starting motor, a free-wheel device, a displaceable pinion connected with said free-wheel deviceand engageable with the engine for starting, a disengageable clutch for connecting said free-wheel device with said inertia mass and a single operating member for controlling said motor, clutch and pinion.

2. A starting device for internal combustion engines comprising a starting motor and a rotatable shaft driven by said motor, an inertia mass mounted on said shaft, a free-wheel device having a driving element and a driven element, loosely mounted on the said shaft and longitudinally displaceable thereon, a pinion secured to the driven element of said free-wheel device and engageable with the engine for starting, a clutch having a driven element secured to the driving element of said free-wheel device and a driving element longitudinally displaceable on said shaft, and a single operating member for controlling said motor, clutch and pinion.

3. A starting device for internal combustion engines comprising an electric motor and a rotatable shaft driven by said motor, an inertia mass secured to said shaft, a switch controlling said electric motor, a free-wheel device having a driving element and a driven element and longitudinally displaceable on said shaft, a pinion connected with the driven element of said free-wheel device and engageable with the engine, a clutch having a driven part secured to the driving element of said free-wheel device and a driving part rotatable by and longitudinally displaceable on said shaft, and a single operating lever operatively connected to the driving part of said clutch and to said switch.

4. A starting device for internal combustion engines comprising an electric motor having a rotor shaft extending therefrom, an inertia mass driven by said electric motor, a .fixed switch contact, a displaceable switch contact, a cam operating said displaceable switch contact having a bridge piece thereon for connecting said contacts to energize said electric motor, a free-wheel device having a driving element and a driven element and longitudinally displaceable on the shaft of said motor, a pinion connected with the driven element of said free-wheel device and engageable with the engine, a clutch having a driving part rotatable by and longitudinally displaceable on the shaft of said motor and a driven part secured to the driving element of said free-wheel device, and a single operating member operatively connected to the driving part of said clutch to operate said clutch and to effect displacement of said pinion into engagement with the engine and operatively connected to said cam to operate said switch contacts.

5. A starting device for internal combustion engines comprising an electric motor having a rotor shaft extending therefrom, an inertia mass driven by said electric motor, a fixed contact, a resilient pivotally mounted yoke, a contact mounted on said resilient yoke, an element displaceable in opposite directions, having a-conducting bridge piece thereon and cam surfaces cooperating with said resilient yoke to displace the contact on said yoke out of engagement with said bridge piece upon actuation of said element in one direction and to effect connection of said fixed contact with said contact on said yoke upon actuation of said element in the other direction to energize said electric motor, a free-wheel device having a driving element and a driven element and longitudinally displaceable on the shaft of said motor, a pinion connected with the driven element of said free-wheel device and engageable with the engine, a clutch having a driving part rotatable by and longitudinally displaceable on the shaft of said motor and a driven part secured to the driving element of said free-wheel device, and a single operating member operatively connected to the driving part of said clutch to operate said clutch and to effect displacement of said pinion into engagement with the engine and operatively connected to said displaceable element to operate said switch contacts.

6. A starting device for internal combustion engines comprising an electric motor having a rotor shaft extending therefrom, an inertia mass secured to the shaft of said electric motor, a switch controlling said electric motor, a free-wheel device having a driving element and a driven element and longitudinally displaceable on the shaft of said motor, a pinion connected with the driven element of said free-wheel device and engageable with the engine, a clutch having a driven part secured to the driving element of said free-wheel device and a driving part rotatable by and longitudinally displaceable on the shaft of said motor, a stop on one part of said clutch engaging the other part to limit their separating displacement /and a single operating lever operatively connected to the driving part of said clutch and to said switch.

7. A starting device for internal combustion engines comprising an inertia mass, a shaft rotatably mounting said mass, an electric motor for setting said inertia mass in rotation at high speed, a pinion freely mounted on said shaft and displaceable longitudinally thereof into and out of engagement with the engine, a clutch having a driving part secured to said shaft for rotation thereby but longitudinally displaceable thereon and a driven part freely mounted on said shaft, 2. driving connection between saiddriven part of said clutch and said pinion, means permitting disengagement of said clutch but so connecting its parts that displacement of said pinion into and out of engagement with the engine may be effected by displacement in opposite directions of the driving part of said clutch, a switch for controlling said motor, and a single'operating lever connected with said switch and the driving part 0! mid clutch and operative to control said motor. clutch and pinion. I

8. A starting device for internal combustion engines comprising an electric motor and a rotatable shaft driven thereby, aninertia mass fixedly mounted on said shaft, a free-wheel device having a driving element and a driven element freely mounted onsaid shalt, a pinionconnected with said driven element and adapted to engage with the engine, a clutch having a driven part freely mounted on said shaftand secured to the driving element of said tree-wheel device and a driving part secured to said shaft for rotation thereby but longitudinally displaceable on said shaft, said clutch, tree-wheel device and pinion being displaceable 'as a whole longitudinally on;

said shaft to dispose said pinion into and out 01' engagement with the engine. switch means for starting'and stopping said motor comprising a variable-throw switch e1 ent eflective only at a position between .two extremes of its' possible movement to close the switch, and a single operating lever connected to said clutch and said switch element'and operative in one extreme of movement in one direction to displace said pin ion along said shaft into engagement with the engine without closing said switch, in a partial reverse movement to disengage the driving part from the driven part'of said clutch and close said switch while said pinion is still in engagement with the engine. in a return to its first-mentioned extreme. position to engage said clutch and open said switch, and in a complete reverse movement to withdraw said pinion from engagement with the engine and open said switch.

' ALBERT CALL-SEN.

ERNST KLEMM. 

